The primary objective of the AVHRR instrument is to provide cloud top and sea surface temperatures through passively measured visible, near infrared and infrared spectral radiation bands. NOAA-6, 8, 10 and TirosN AVHRR sensors measured in 4 spectral bands, while the NOAA 7 and 9 AVHRR instruments measured in 5.

Measurements made by the sensor have a 10 bit precision and the data itself is available as a Level 1b data product from National Environmental Satellite Data and Information Services, Satellite and Data Services Division (NESDIS/SDSD) in Suitland, Maryland.

Full Resolution Level 1b Data:

The Level 1b data format corresponds to quality controlled raw AVHRR data, that is assembled into discrete data sets with sensor calibration and earth location information appended to the incoming radiation (video) data (NOAA Polar Orbiter Data Users Guide). At URI all Level 1b data is stored on 6250bpi computer compatible tapes. The data tapes originate at NESDIS/SDSD in Suitland, Maryland and the University of Miami Rosenstiel School of Marine and Atmospheric Science, Miami, Florida. The two processing facilities support slightly different data tape formats, the NESDIS/SDSD format is a packed data format and is described in the NOAA Polar Orbiter Data User Guide, whereas the Miami format is unpacked to facilitate quicker tape to disc transfer.

The TIROS-N/NOAA series satellites have two operational modes for collecting and transmitting full resolution AVHRR data. The normal operating mode is direct transmission in real time to receiving stations within line of sight of the orbiting satellite. This direct transmission data is called HRPT for High Resolution Picture Transmission. The second full resolution mode is LAC or Local Area Coverage. LAC data is recorded and stored on-board the satellite for later transmission. LAC data coverage is scheduled by NOAA/NESDIS and may be recorded over any portion of the world. The primary receiving stations for HRPT data are Wallops Island, Virginia and Gilmore Creek, Alaska. The data collected by these two stations is permanently stored on magnetic tape at the NESDIS data facility in Suitland, Maryland. Based on these two stations HRPT areal coverage is of the western North Atlantic west from about 50W, and north of 18N, the Gulf of Mexico, north of 18N and the Gulf of Alaska in the North Pacific. In July of 1987 HRPT collected at the NESDIS facility in Redwood City, California became available. This archive will contain AVHRR passes of the west coast of North America from 1984 to the present in standard Level 1b format. The Naval Ocean Research and Development Activity facility at NSTL, Mississippi has a non-permanent 90 day rotating HRPT archive of data collected over the Gulf of Mexico.

The majority is HRPT at full resolution, 4 or 5 channel, full pass (complete 10-15 minute direct transmission reception) data sets. Copies of the data are available as is, (i.e. complete data set in the original data tape format).